Modified aliphatic superplasticizer and preparation method thereof

Abstract

The invention relates to a modified aliphatic superplasticizer and a preparation method thereof. The prepared aliphatic superplasticizer has high water-reducing rate, small concrete slump loss and good cement adaptability. The preparation method of the modified aliphatic superplasticizer comprises the following steps of: (1) modifying agent preparation: dissolving acrylamide, sodium sulfite and water through heating, and slowly dripping formaldehyde in one hour; thermally insulating for 3 hours after the dripping is finished, cooling and discharging to obtain a sulfomethylation acrylamide modifying agent; (2) modified aliphatic superplasticizer preparation: stirring the sodium sulfite with water to dissolve; dripping acetone in half an hour; adding initiating agent solution which is prepared in advance; slowly dripping formaldehyde which accounts for about 1 / 3 of the total volume; then, quickly dripping the residual formaldehyde and the modifying agent, finishing the dripping in an hour, and continuously retaining heat for 2 hours; and finally, adding water to cool and discharging to obtain the brownish red liquid modified aliphatic superplasticizer.

Description

technical field [0001] The invention relates to a modified aliphatic high-efficiency water reducer and a preparation method thereof, belonging to the technical field of building materials. Background technique [0002] Concrete superplasticizers have become an important component of high-performance concrete. At present, in the domestic market, the high-efficiency water reducers are mainly naphthalene-based and polycarboxylic acid-based. The latter is mainly used in high-performance concrete such as passenger lines due to its high price. Water reducing agent, etc. The disadvantage of naphthalene-based superplasticizers is that the slump loss is large, and due to the high content of sodium sulfate, crystallization and precipitation are prone to occur in low-temperature environments, which seriously limits its use in winter; The price of water agent is high, it is sensitive to the dosage at low dosage, and it is incompatible with naphthalene-based water reducers, etc., which...

AI Technical Summary

Problems solved by technology

The reaction mechanism of aliphatic high-efficiency superplasticizers is complex. Many monomers and process formulas can be used to synthesize aliphatic high-efficiency water-reducers. The performance of corresponding products is also very different. Although there have been many studies on its modification, but There is still a lot of room for modifying the performance of aliphatic high-efficiency water reducers by introducing new monomers